Printer Vulnerability Exposed by Indiana U Security Engineer

• By Dian Schaffhauser
• 04/08/08

Security engineers in the Information Technology Security Office (ITSO) at Indiana University were at a loss when a user described a network-connected multifunctional printer that was acting strangely--even printing spam e-mail messages onto paper.

While investigating the printer problem, Nate Johnson, Indiana U's lead security engineer, took a chance and tested the printer for vulnerability to a File Transfer Protocol (FTP) Bounce Attack, a method used by malicious computer hackers to relay a network scan through another device, essentially covering their tracks online.

Johnson's hunch paid off, and with the maneuver, he discovered a security risk in a widely used family of Canon printers.

ITSO provides active security analysis, development, education, and guidance related to Indiana U's information assets and IT environment.

Johnson and ITSO recently published the vulnerability, having already alerted Canon to the problem. UISO has published four disclosures in the last two years.

Johnson's test--a common tactic for security professionals hoping to find holes in network security--revealed a vulnerability in the network configuration of certain printers and other devices in the Canon imageRUNNER series. These multifunctional printers are the size of a traditional copying machine and include network access that can leave them open to misuse if not properly configured. Hackers can exploit the device's Internet connection and treat it as a proxy from which to attack other sources, while concealing their own location.

"I stumbled across the security vulnerability," said Johnson. "The customer was having a problem with a printer, and on a whim I tested it. Hopefully, now that we have published the risk, people and businesses with these devices will take another look at their inventory."

Workarounds to the vulnerability include disabling FTP printing, setting up a username and password challenge to protect FTP printing or having a Canon service technician install a firmware update. A report posted on the campus' security office site states, "Additionally, best practices suggest that access controls and network firewall policies be put into place to only allow connections from trusted machines and networks."

According to Canon, the FTP command isn't used for printing from the printer driver. It only affects those imageRUNNER machines that have the FTP print setting on.

To view the detailed alert reported by UISO, visit   https://itso.iu.edu/20080229_Canon_MFD_FTP_bounce_attack.

To view the alert from Canon, visit  http://www.usa.canon.com/html/security/office_security.html.